Cellular Respiration and Fermentation
  1. Mitochondria- powerhouse of the cell that makes ATP; similar to chloroplast because has inner membrane (like thylakoid membrane) and matrix (similar to stroma) Mitochondria is a plastid and looks similar to bacteria; Mitochondria and chloroplasts both have separate sets of DNA. Parasite- something that lives off of its host and gives it harm Symbia- balanced relationship Mitochondrial DNA comes from eggs of the mother
Respiration
  • The importance of membranes to respiration is that they possess the electron transport chain and keeps the electrons in a hydrophobic environment. Separates the hydrogen ions and allows a gradient to be created; thus, providing more surface area for more reactions Transport- Ex: Hydrogen-Ion Pump fueled Gradient makes potential energy ATP synthetase uses the H+ gradient to make ATP potential energy becomes chemical energy Membranes are crucial to process…
  • Plastids:
    • Mitochondria and chloroplast
    • Characteristics
      • contain DNA
      • lots of internal membranes- crucial part of respiration
    • Differences:
      • Chloroplasts
        • CO2→glucose 2. (Glucose→pyruvate)
        • Chloroplasts take in photons of light and give off glucose and oxygen
      • Mitochondria
        • pyruvate→CO2
        • takes in glucose and oxygen and gives off H20, carbon dioxide and ATP is released (Aerobic respiration)
        • Mitochondria comes from the mother
        • Matrix is the internal fluid of the mitochondria
    • Plastids may have derived from symbiotic relationships ibetween bacteria and primitive eukaryotic cells
      • Bacteria provides things that protect the cells
      • cells help bacteria function
Photosynthesis and Respiration:
  • Photosynthesis:
    • Some protists, bacteria and most plants do it;
  • Respiration:
    • every organism does it in order to get energy to perform certain actions
    • The three steps of Respiration:
      1. Glycolosis- 2 ATP’s;
      2. Krebs Cycle (2 ATPs)
      3. Electron Transport Chain (34 ATPs; most energy during breaking down glucose Respiration Cycle: Glucose> Glycolysis (Fatty Acids don’t go into glycolosis)> Krebs Cycle(2 ATPs)> Electron Transport Chain (34 ATPa) Glycolysis(happens in Cytoplasm) Anaerobes do this - Glucose is converted into 2 molecules of pyruvate; 2 ATP and 2 NADH(similar to NADPH) are produced Krebs Cycle (happens in mitochondia); Aerobes do this and CO2 is given off- Converts pyruvate into CO2; Produces more ATP and NADH; Creates another energy called FADH; 1 ADP is converted into 1 ATP; 4 NAD+ are converted into 4NADH; For every molecule of glucose; 2 ATPs are made Aerobic Respiration- has access to oxygen; Anaerobic respiration- No access to oxygen Every organism on the planet does some form of glycolysis Chloroplast membranes: Thylakoid membranes, Thylakoid compartment, Stromal compartment Mitochondria membranes- Inner membrane, Outer membrane and Matrix Importance of Membranes in cellular respiration Allow for exchange of materials with the environment Allows build-up of H+ ions, gradient (concentration, electrical) Allows certain molecules to be retained in the organelle so they don’t have to be produced again; H+, ATP, NADH, FADH2, Krebs cycle on internal membrane Electron Transport Chain –In the membrane, secluded from aqueous environment. H+ ions go through the ATP synthetase (resides in the membrane, powered by the H+ gradient) Electron transport chain-keeps the electrons in a hydrophobic environment Separates the H ions, allows a gradient to be created, gradient=potential energy ATP synthetase uses H+ gradient to make ATP, potential energy becomes chemical energy Provides surface area—room for reactions in electron transport chain Transport— example=H+ ion pump fueled by electron transport Krebs cycle can convert all carbon that enters to carbon dioxide Aerobic respiration liberates the most energy in the form of ATP Glycolysis depends on a supply of NADH The breakdown of pyruvate in the Krebs Cycle results in the release of energy and carbon dioxide During the third stage of aerobic respiration 32 ATPs are formed. Glucose is converted into glycogen in the muscles and liver



Cellular Respiration and Fermentation

Cellular Respiration Review

1. Which of the following processes produces the most ATP molecules per glucose molecule consumed?

a. Krebs Cycle
b. electron transport
c.chemiosmosisc.
d.glycolysis

2. The purpose of cell respiration is to:

a. synthesize carbohydrates from CO2 b. break down carbohydrates to provide energy for the cell c. provide oxygen for the cell

3. The NET RESULT of glycolysis is:

a. 4ATP and 4NADH
b. 4ATP and 2NADH
c. 2ATP and 2 NADH

4. In the course of the Krebs Cycle, how many molecules of ATP are produced?

a. 2
b. 4
c. 36
Matching
6. The process by which glucose is split into pyruvate.
7. The process by which a hydrogen gradient is used to create ATP
8. A process that makes a small amount of ATP and produces lactic acid
9. A series of membrane embeddded eletron carriers that ultimately create the hydrogen ion gradient to drive the synthesis of ATP
10. The process by which the breakdown of glucose is completed and CO2 is produced
11. The process that does NOT occur in the mitochondria
12. Also known as the Citric Acid Cycle
13. Starts with Acetyl-CoA


Choices for 6-13

a. chemiosmosis
b. Electron transport chain
c. Krebs Cycle
d. Glycolysis
e. Fermentation


14. Muscle fatigue is caused when the process of fermentation produces:
a. ethanol
b. lactic acid
c. ATP

15. For each molecule of glucose broken down, the Kreb's cycle must make _ complete turns.
a. 2
b. 4
c 36

  • Mitochondria- powerhouse of the cell that makes ATP; similar to chloroplast because has inner membrane (like thylakoid membrane) and matrix (similar to stroma)
  • Mitochondria is a plastid and looks similar to bacteria; Mitochondria and chloroplasts both have separate sets of DNA.
  • Parasite- something that lives off of its host and gives it harm
  • Symbia- balanced relationship
  • Mitochondrial DNA comes from eggs of the mother
  • Respiration
  • The importance of membranes to respiration is that they possess the electron transport chain and keeps the electrons in a hydrophobic environment.
  • Separates the hydrogen ions and allows a gradient to be created; thus, providing more surface area for more reactions
  • Transport- Ex: Hydrogen-Ion Pump fueled
  • Gradient makes potential energy
  • ATP synthetase uses the H+ gradient to make ATP potential energy becomes chemical energy
  • Membranes are crucial to process…
  • Both a Mitochondria and a chloroplast are Both: “plastids”, contain DNA, lots of internal membranes- crucial part of respiration
  • Differences: 1. Chloroplasts CO2glucose 2. (Glucosepyruvate)  Mitochondria pyruvateCO2
  • Chloroplasts take in photons of light and give off glucose and oxygen; the mitochondria takes this in and gives off H20, carbon dioxide and ATP is released (Aerobic respiration).
  • A symbiotic relationship is present: Bacteria provides things that protect the cells and cells help bacteria function
  • Mitochondria comes from the mother; Matrix is the internal fluid of the mitochondria
  • Photosynthesis: Some protests, bacteria and most plants do it; Respiration: everyone does it in order to get energy to perform certain actions
  • The three steps of Respiration: Glycolosis- 2 ATP’s; Krebs Cycle (2 ATPs) and Electron Transport Chain (34 ATPs; most energy during breaking down glucose
  • Respiration Cycle: Glucose> Glycolysis (Fatty Acids don’t go into glycolosis)> Krebs Cycle(2 ATPs)> Electron Transport Chain (34 ATPa)
  • Glycolysis(happens in Cytoplasm) Anaerobes do this - Glucose is converted into 2 molecules of pyruvate; 2 ATP and 2 NADH(similar to NADPH) are produced
  • Krebs Cycle (happens in mitochondia); Aerobes do this and CO2 is given off- Converts pyruvate into CO2; Produces more ATP and NADH; Creates another energy called FADH; 1 ADP is converted into 1 ATP; 4 NAD+ are converted into 4NADH; For every molecule of glucose; 2 ATPs are made
  • Aerobic Respiration- has access to oxygen; Anaerobic respiration- No access to oxygen
  • Every organism on the planet does some form of glycolysis
  • Chloroplast membranes: Thylakoid membranes, Thylakoid compartment, Stromal compartment
  • Mitochondria membranes- Inner membrane, Outer membrane and Matrix




Importance of Membranes in cellular respiration
  1. Allow for exchange of materials with the environment
  2. Allows build-up of H+ ions, gradient (concentration, electrical)
  3. Allows certain molecules to be retained in the organelle so they don’t have to be produced again; H+, ATP, NADH, FADH2,
  4. Krebs cycle on internal membrane
  5. Electron Transport Chain –In the membrane, secluded from aqueous environment.
  6. H+ ions go through the ATP synthetase (resides in the membrane, powered by the H+ gradient)
  7. Electron transport chain-keeps the electrons in a hydrophobic environment
  8. Separates the H ions, allows a gradient to be created, gradient=potential energy
  9. ATP synthetase uses H+ gradient to make ATP, potential energy becomes chemical energy
  10. Provides surface area—room for reactions in electron transport chain
  11. Transport— example=H+ ion pump fueled by electron transport
  12. Krebs cycle can convert all carbon that enters to carbon dioxide
  13. Aerobic respiration liberates the most energy in the form of ATP
  14. Glycolysis depends on a supply of NADH
  15. The breakdown of pyruvate in the Krebs Cycle results in the release of energy and carbon dioxide
  16. During the third stage of aerobic respiration 32 ATPs are formed.
  17. Glucose is converted into glycogen in the muscles and liver

“In all cells, all of the main energy-releasing pathways start with the same reactions in the cytoplasm.”

Pathways are enzyme catalyzed

Glycolysis --> Metabolic Reactions run on energy released from glucose other organic compounds

· Glucose (6 carbon backbone) --> 2 Pyruvate (3 carbon backbone)

  • · In the cytoplasm
  • · Yields 2 ATP



Aerobic pathway
· Mitochondria
· Oxygen dependent--Oxygen accepts and removes electrons
· 3 reaction stages
  • · Glycolysis 2 ATP
  • · Krebs cycle 2 ATP
  • · Electron transfer phosphorylations 32 ATP

· Net yield 36 ATPs


Electron and Hydrogen transfer
· NAD+ (oxidized form)--> NADH (reduced form)
· FAD+ (Oxidized form) --> FADH2 (reduced form)

Anaerobic pathway--> completed in the cytoplasm
· Net yield 2 ATPs/glucose

Glycolysis:

  • Glucose (C6H12O6) + 2 ATP -->2 PGAL --> 2 PGA --> 2 Pyruvate (C3) + NADH + 4 ATP (net yield 4ATP-2ATP 2 ATP)

  • Glycolysis is a metabolic pathway that is found in the cytoplasm of cells in all living organisms and does not require oxygen. The process converts one molecule of glucose into two molecules of pyruvate, and makes energy in the form of two net molecules of ATP. Four molecules of ATP per glucose are actually produced; however, two are consumed for the preparatory phase. The initial phosphorylation of glucose is required to destabilize the molecule for cleavage into two triose sugars. During the pay-off phase of glycolysis four phosphate groups are transferred to ADP to make four ATP; and two NADH are produced when the triose sugars are oxidized. Glycolysis takes place in the cytoplasm of the cell. The overall reaction can be expressed this way:

Krebs cycle:
  • 2 turns of the Kreb cycle (2 Pyruvate --> 2 acetyl-CoA --> 6 CO2)
  • 2 NADH + 6 NADH + 2 FADH2

Electron Transfer Phosphorylation
  • · NADH and FADH2 --> H+ + electrons
  • · Electrons--> electron transfer, H+ pump pumps H+ from inner to outer compartment
  • · [H+] in outer compartment rises and drives ATP formation (ATP Synthetase)

question
  • which liberates the most energy in the form of ATP? Electron Transport chain
  • Aerobes use as the final electron transport acceptor in the electron transport phosphorylation (electron transport chain). (#9) oxygen
  • Glycolysis depends on a continuous supply of (#10) ATP
  • How many ATPs typically form during the third stage of aerobic respiration? (#20) 34
  • When blood glucose levels decrease (as between meals) what reserves are tapped? (#21) glycogen
  • Glucose is converted into glycogen in the _ (#22) Liver
  • Fermentation- both kinds. we never talked about either one fermentation pathways anaerobic pathways

Great diagram for electron transport system http://content.answers.com/main/content/wp/en/thumb/9/92/400px-Etc2.png

Why are membranes important in respiration?
  • - Allow for exchange of materials with the environment - Transport
  • - Allows build - up of H+ ions, which builds up an electrical gradient (2 types of gradients - electrical, concentration)
  • - Allows certain molecules to be retained in the membrane so that they don't have to be produced again = H+, ATP, NADH, FADH2
  • - Krebs Cycle happens on the internal membrane.
  • - Electron transport chain is in the membrane, so that it is away from the water. Electron transport chain doesn't work in an aqueous environment.
  • - H+ ions go through the ATP synthetase (resides in the membrane, powered by the H+ gradient)
  • - Provides surface area - The more surface area, more energy that is able to be created

IMPORTANT VOCABULARY:
  1. Mitochondria- powerhouse of the cell that makes ATP (Mitochondrial DNA comes from eggs of the mother)
  2. Parasite- something that lives off of its host and gives it harm
  3. Symbia- balanced relationship
  4. Aerobic-needs oxygen
  5. Anaerobic-does not need oxygen (Oxygen may in fact be poisonous)

Here's the link to some powerpoints that go into a bit more detail and discuss fermentation. They may be able to clear up some confusion.

Mitochondria are membrane-enclosed organelles distributed through the cytosol of most eukaryotic cells. Their number within the cell ranges from a few hundred to, in very active cells, thousands. Their main function is the conversion of the potential energy of food molecules into ATP. external image Mitochondrion.gif Mitochondria have:
  • an outer membrane that encloses the entire structure
  • an inner membrane that encloses a fluid-filled matrix
  • between the two is the intermembrane space
  • the inner membrane is elaborately folded with shelflike cristae projecting into the matrix.
  • a small number (some 5–10) circular molecules of DNA
The number of mitochondria in a cell can
  • increase by their fission (e.g. following mitosis);
  • decrease by their fusing together.
(Defects in either process can produce serious, even fatal, illness.)

The

The outer membrane contains many complexes of integral membrane proteins that form channels through which a variety of molecules and ions move in and out of the mitochondrion.

The inner membrane contains 5 complexes of integral membrane proteins:
  • NADH dehydrogenase (Complex I)
  • succinate dehydrogenase (Complex II)
  • cytochrome c reductase (Complex III; also known as the cytochrome b-c1 complex)
  • cytochrome c oxidase (Complex IV)
  • ATP synthase (Complex V)

The matrix contains a complex mixture of soluble enzymes that catalyze the respiration of pyruvic acid and other small organic molecules.
Here pyruvic acid is
  • oxidized by NAD+ producing NADH + H+
  • decarboxylated producing a molecule of
    • carbon dioxide (CO2) and
    • a 2-carbon fragment of acetate bound to coenzyme A forming acetyl-CoA